WATCH: Screaming students flee classroom as teacher chops off boy’s hair while belting out the National Anthem

A California teacher is behind bars, facing child endangerment charges, after videos emerged that show her forcibly cutting several students' hair—then belting the national anthem, reports the Visalia Times Delta.

The teacher had been acting in an erratic manner all week, prompting students to reach out to school authorities. But they failed to reprimand her.

Science teacher Margaret Gieszinger, 52, chopped off a student's hair, even as he tried to move away from her. She threw the hair behind her back. When she started going after other students they ran out of the classroom screaming.

As the students ran out of the room, Gieszinger continued belting out the national anthem.

While parents and students were appalled by the behavior, others came to her defense.

"When everything was going on I was terrified, and I so badly wanted to blame her. I was scared she was going to come back," a student told the Times Delta. "What she did to my classmates and I is inexcusable. I am not trying to make excuses for her, I simply ask everyone to reconsider how they view her. She is a loving and kind lady. She is usually all smiles and laughs. This is not the Miss G. we know and love."

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